Sunday, December 07, 2008

What is this 6502-based device?

While I was a student at the University of Waterloo I used to go to the surplus sales. This is one of the more unusual things I picked up. It used to belong to the psychology department, and it still has stickers from psychology experiments. I suppose it was used to collect data in experiments.It is from Observational Systems Inc. in Seattle, WA. Inside are several circuit boards. Here is the main board, with the 6502 processor, EPROM, RAM and I/O.Here is the board with the keypad and LCD. Along the top are a lot of LCD driver ICs.Finally, here is the rest of the device, with the backplane and a small daughterboard for the CPU board which contains some analog electronics.The device seems to require 5V power. It does turn on, but it doesn't seem to function consistently so I think it is probably broken. Occasionally I'm tempted to take it apart and build a new 6502 based system from it. The CPU was used in many 8-bit home computers, including the Apple I, Apple II, Commodore PET and more, so there is plenty of information available on it.